// 原型链继承
class Parent {
  constructor() {
    this.name = "coderqian";
    this.sex = "男";
    this.arr = [1, 2, 3];
  }
}
function Child() {}
Child.prototype = new Parent();
Parent.prototype.say = "ccccc";
let child = new Child();
let child1 = new Child();
child.name = "ccc";
child.arr.push(22);
console.log(child.arr);
console.log(child1.arr);
